Professional Observation

Observation Details

Signs of Unstable Snow

Snow Stability

Key Points

Toured out of JMSA today out to the Negatives.

• N facing terrain BTL had a somewhat breakable rain/temperature crust over faceted snow at 9600′ approaching the Hourglass.
• Skies were mostly clear with passing high, thin clouds throughout the day.
• The Hourglass itself held firm snow throughout, with some softening at about 1100 on the climbers right side. Moving onto less sun exposed terrain in the choke and on the bench above proved to be a skin glopping, ski crampon clogging experience whenever I encountered a skiff of dry snow.
• Winds were light out of the W topping out the Negatives ridgeline at 11200′ around noon with temps at about 37F. All around a warm and beautiful day in the high country!
• I skied a confined E facing couloir at about 1230. I had few stability concerns as I was only able to kick off a few small rollerballs. Ski pen was never more than a couple inches. The right sidewall which had some fresher snow was more prone to being sticky and producing small rollerballs running a short distance.
• Another party reported hearing small rockfall in the area earlier in the morning. I did see evidence of scattered previous rockfall, but didn’t have anything come down around me on my short descent.
• More due south aspects had cooked down to a supportable surface with reduced ski-pen, but still great skiing.
• North facing terrain NTL proved to be more punchy as the day progressed and the crust became more breakable. The facets beneath seemed to be getting slightly moist beneath the crust and the skiing was generally more unpleasant.